Task 2

Hello again..

As I mentioned in my previous post, I have to mention about the things that I learn in this second semester for science computer. So lets get started.


Last week I learned about NETWORK. What is network is mainly about? Well , Network is a collection of computers and devices connected together via communications devices and transmission media. 

THE APPLICATION OF NETWORK

Resource sharing ( hardware and software)

Information sharing ( easy accessibility from anywhere, search capability)

Communication (email, message broadcast)

Communication Device

A communications device is any type of hardware capable of transmitting data, instructions, and information between a sending device and a receiving device.

There are various type of communication device

• Dial-up Modem

A communications device that can convert digital signals to analog signals and analog signals to digital signals, so that data can travel along an analog telephone line.

• Digital modem

A communications device that sends and receives data and information to and from a digital line.

• Wireless modem

Some mobile users have a wireless modem that uses the cell phone network to connect to the Internet wirelessly from a notebook computer, a smart phone, or other mobile device.

• Network card

Sometimes called a network interface card, is a communications device that enables a computer or device that does not have built-in networking capability to access a network.

• Wireless access point

A central communications device that allows computers and devices to transfer data wirelessly among themselves or to transfer data wirelessly to a wired network .

*Wireless access points have high-quality antennas for optimal signals.

• Router

A communications device that connects multiple computers or other routers together and transmits data to its correct destination on a network.

• Switch

A connection device similar to a hub but more sophisticated, including functionality that allows it to control and manage data transmissions.

• Hub

A connection device that allows multiple connections to the network

Figure shows the connection between devices ( router, modem and computer in a network)

Transmission media

There are two types of transmission media, which is

1.Physical transmission media/Guided media/Wired

•Twisted-Pair CableCoaxial Cable, Fiber-Optic Cable.

2.Wireless transmission media/Unguided media/ Wireless

Infrared

Infrared (IR) is a wireless transmission medium that sends signals using infrared light waves.

Broadcast Radio ( Bluetooth, Ultra Wideband (UWB),Wi-Fi, WiMAX)

A wireless transmission medium that distributes radio signals through the air over long distances

such as between cities, regions, and countries and short distances such as within an office or home.

Cellular Radio( 2G, 3G, 4G, 5G)

A form of broadcast radio that is used widely for mobile communications, specifically wireless modems and cell phones

Microwave

Microwaves are radio waves that provide a high-speed signal transmission.

* Microwave transmission, often called fixed wireless, involves sending signals from one microwave station to another.

 Communications satellite

Is a space station that receives microwave signals from an earth-based station, amplifies (strengthens) the signals, and broadcasts the signals back over a wide area to any number of earth-based stations.

SHARING HARDWARE
It can reduce the cost of purchasing hardware



SHARING SOFTWARE
It can reduce the cost of buying software




SECURITY
A network can be password protected and can only be accessed by authorized users.




SPEED
Sharing and transferring files within network is very rapid

                       Breakdown and possible loss of resources
                         Breakdown of the whole network due to an issue of the server may lead to loss of important                   data of the server.

                          Expensive to Build

                          Building a network  for large scale organizations are very pricey especially to buy and replace                                cables and other hardware

                         Security Threats

               There are hackers who are trying to steal valuable data of large companies for their own benefit.

              Bandwidth issue

               Heavy users who consume a lot more bandwidth will affect other users.

I hope that this information will gain your knowledge in computer